text: import React, {Component, PropTypes} from 'react'
  
  const Counter = ({value, onIncrement, onDecrement, onIncrementAsync}) =>
      <div>
          <button onClick={onIncrement}>
              Increment
          </button>
          {' '}
          <button onClick={onDecrement}>
              Decrement
          </button>
          <button onClick={onIncrementAsync}>
              Increment after 1 second
          </button>
          <hr/>
          <div>
              Clicked: {value} times
          </div>
      </div>
  
  Counter.propTypes = {
      value: PropTypes.number.isRequired,
      onIncrement: PropTypes.func.isRequired,
      onDecrement: PropTypes.func.isRequired
  }
  
  export default Counter
  